The bactericidal effect of antibiotics causes. The mechanism of action of nitrofurans

The balance of the body between health and disease is called Homeostasis.

Homeostasis largely depends on the body's attitude to the bacteria with which it lives. For example, bacteria are always present on human skin.

When the skin is injured, bacteria can enter the body and can cause infection. The invasion of bacteria usually destroys the phagocytes.

Phagocytes- cells of the immune system that protect the body by absorbing (phagocytosis) harmful foreign particles, bacteria, as well as dead or dying cells. However, when there are too many bacteria in the body for processing, disease occurs and antibiotics are needed to help restore homeostasis.

Antibiotics can be bacteriostatic (prevent bacteria from growing) or bactericidal (kill bacteria).

Bacteriostatic action characterized by the ability of antimicrobial agents to interfere with the metabolic-enzymatic processes of the pathogen (blocking oxidative processes, growth substances, etc.), disrupt its growth and reproduction. Some bacteriostatic agents, with increasing concentration, have a bactericidal effect. Bacteriostaticity is characterized by the selectivity of action against certain types of bacteria.

Bactericidal action medicines- the ability of some antibiotics, antiseptic and other drugs to cause the death of microorganisms in the body.

The mechanism of bactericidal action, as a rule, is associated with the damaging effect of these substances on the cell walls of microorganisms, leading to their death.

For most infections, these two types of antibiotics are equally effective, but if the immune system is compromised or the person has a severe infection, bactericidal antibiotics are usually more effective. Bactericidal drugs can have a bacteriostatic effect against certain microorganisms, and vice versa.

In most infections, including some types of pneumonia (pneumococcal) and infections urinary tract, there is no advantage between bactericidal and bacteriostatic drugs. Nevertheless, bactericidal activity is necessary for infections in which the host of the organism, from which the bacteria get their food, defense mechanisms were partially absent locally or systemically (in the entire system), for example, endocarditis (inflammation of the inner lining of the heart membrane), meningitis (inflammation of the membranes spinal cord or brain), or serious staphylococcal infections.

Each of the different types of antibiotics kill microorganisms in different ways.

1. Disrupt the structure of the bacterial cell wall;
2. Interfere with the production of essential proteins;
3. Interfere with the transformation (metabolism) of nucleic acid (substances contained in the cells of all living things);

Testing the effects of antibiotics in a laboratory shows how much exposure to a drug is needed to reduce bacterial growth or to kill bacteria. A large dose of an antibiotic taken at one time can kill the bacteria that cause disease, but a large dose is likely to cause serious side effects. Thus, antibiotics are given in small doses. This method ensures that the bacteria are either killed or sufficiently reduced in number so that the body can fight on its own. On the other hand, when too little antibiotic is taken, bacteria can develop methods to protect themselves from it. Thus, the next time the same antibiotic is needed against these bacteria, it will not be effective.

Conclusion: antibiotics should be taken as prescribed by a doctor, strictly according to instructions.

Attention! Before using drugs it is necessary to consult a doctor. The information is provided for informational purposes only.

Hg 2+. Cu 2+), chemotherapeutic agents (sulfonamides, arsenic preparations) and other substances that completely inhibit the multiplication of bacteria or other microorganisms, i.e., cause bacteriostasis. B.'s action. reversible: when they are removed or added inactivators B. c. bacterial growth resumes. For example, the action of metal ions is terminated in the presence of hydrogen sulfide, which frees the surface of bacterial cells from them. B.'s action. also stop substances with a high adsorption capacity (for example, proteins). This explains the decrease in B.'s activity of century. blood, pus, etc. Bactericidal substances also have a bacteriostatic effect in low concentrations. By inhibiting the reproduction of pathogenic microbes in the human or animal organism, B. c. act as medications. With the help of B. of century harmless to the person. protect various foodstuffs, grape must, milk, etc. For this, benzoic acid, fumigation with sulfur dioxide, hydrogen peroxide, and various antibiotics not used in medical practice are used.

Great Soviet Encyclopedia. - M. Soviet Encyclopedia. 1969-1978.

See what Bacteriostatic substances are in other dictionaries:

BACTERIOSTATIC SUBSTANCES - bacteriostatics, substances with the ability to temporarily stop the reproduction of bacteria. They are allocated by many microorganisms (actinomycetes, fungi), as well as by some higher plants; have a regulatory effect on populations ... Ecological Dictionary

Bacteriostatic agents b means - Bacteriostatic agents b. means * bacteriastatic agents, b. akin * bacteriostatic agents or b. remediums substances that stop or slow down the growth of bacteria, but do not kill them. These include sulfa drugs ... Genetics. encyclopedic Dictionary

Bacteria - (Greek bakterion bacillus) a large group (type) of microscopic, predominantly unicellular organisms with a cell wall, containing a lot of deoxyribonucleic acid (DNA), having a primitive nucleus devoid of visible ... Great Soviet Encyclopedia

Bacteriostasis - (from Bacteria and Greek stasis standing in place) a complete inhibition of the growth and reproduction of bacteria caused by unfavorable physical or chemical factors or the lack of necessary conditions for their growth (humidity, temperature, pH ... Great Soviet Encyclopedia

Antibiotics - I Antibiotics (Greek anti against + bios life) substances formed by microorganisms, higher plants or tissues of animal organisms, as well as semisynthetic and synthetic analogs of these substances, selectively suppressing the development ... Medical encyclopedia

Antibiotics - Test for the sensitivity of bacteria to different antibiotics. On the surface of the Petri dish, on which bacteria grow, it is better ... Wikipedia

Tetracyclines - The basic chemical structure of tetracyclines Tetracyclines # 160; (eng. # 160; tetracyclines) a group of antibiotics belonging to the class of polyketides, similar in chemical structure and biological properties ... Wikipedia

Flemoklav Solutab - Active ingredient ›› Amoxicillin * + Clavulanic acid * (Amoxicillin * + Clavulanic acid *) Latin name Flemoclav Solutab ATX: ›› J01CR02 Amoxicillin in combination with enzyme inhibitors Pharmacological group: Penicillins in ... Dictionary of Medicines

Silver - This term has other meanings, see Silver (disambiguation). 47 Palladium ← Silver → Cadmium ... Wikipedia

Needles - Spruce branch with needles and young cones. Needles are leaf-like organs of many gymnosperms (coniferous) plants of pine, spruce, thuja, etc. Juvenile needles of thickets ... Wikipedia

Medical College

Considered and approved at the meeting of the CMK Protocol No.__ "__" _________ 2015. Chairman of the CMC ___________ E. Levkovskaya

Examination ticket No. 6 Intermediate exam OP 07. "Pharmacology" in the specialty: 34.02.01 "Nursing" VET basic training

APPROVED Director of the Medical College __________ Maletin O.V. "__" ____________ 2015

1. Antibiotics, features of therapy, the concept of resistance, bactericidal and bacteriostatic effect. The main groups of antibiotics.

2. Classification of antihypertensive drugs. Mechanisms and localization of action of antihypertensive drugs of different groups (neurotropic, myotropic action and affecting the water-salt balance).

3. Write out a prescription: 5 tablets of Warfarin, 0.025 g each.

4. Name a remedy for relieving an attack of angina pectoris.

5. A woman, 23 years old, was taken to the maternity hospital in connection with the onset of labor. The woman in labor has rare short-term contractions of the uterus. Weakness diagnosed generic activity... What hormonal drug could be included in medication regimens for the stimulation of labor?

1. Antibiotics features of therapy, the concept of resistance, bactericidal and bacteriostatic effect

Antibiotics- Substances of predominantly microbial origin, their semi-synthetic or synthetic analogs suppressing the vital activity of microorganisms sensitive to them.

§ Antibiotics are prescribed based on culture and antibiotic susceptibility testing.

§ The course of therapy should last an average of 5-7 days.

§ In combination with antibiotics, it is necessary to prescribe drugs to normalize the intestinal microflora, antiallergic drugs and vitamins.

Resistance- resistance (resistance, immunity) of the body to the effects of various factors. Bactericidal effect- This is an effect aimed at destroying bacteria. Antibiotics with bactericidal action: penicillins, cephalosporins, carbapenems, monobactams, aminoglycosides.

Bacteriostatic effect- This is an effect aimed at stopping the multiplication of bacteria in the body. Antibiotics with bacteriostatic action: macrolides, tetracyclines, chloramphenicol.

2. Antihypertensive (antihypertensive) drugs lower systemic blood pressure. The action of the funds is aimed at reducing the work of the heart, reducing the tone of arterial vessels, and the volume of circulating blood. Restricting the intake of SODIUM CHLORIDE with food reduces blood pressure, therefore, a salt-free diet is recommended for the treatment of hypertension.

1. Means that reduce the stimulating effect of adrenergic innervation on the cardiovascular system (neurotropic drugs):

Beta-blockers Metoprolol, Bisoprolol.

Alpha-blockers: Prazosin, Tropafen, Tamsulosin.

Sympatholytics: Reserpine, Octadin, Ornid.

Ganglion blockers: Pentamin, Pachikarpin.

2. Drugs affecting the renin-angiotensive system

ACE inhibitors: Captopril, Enalapril.

Angiotensin receptor blockers: Losartan and Valsartan.

3. Vasodilator drugs of direct myotropic action

Vasodilators Papaverine, Dibazol.

4. Drugs affecting water-salt metabolism (diuretics)

Loopback: Furosemide, Torasemide.

Thiazide Indapamide, Hypothiazide.

5. Calcium antagonists: Nifedepine, Amlodipine.

6. Stimulants of imidazoline receptors Moxonidine.

7. Alpha 2adrenomimetics of the central type of action Clonidine has a sedative, hypnotic effect.

3. Warfarin - an indirect type of anticoagulant

The bacteriostatic effect of antibiotics is

Bacteriostatic antibiotics

Tetracyclines are divided into biosynthetic and semi-systhetic.

Biosynthetic tetracyclines are a waste product of radiant fungi. Their structure is based on a condensed four-cyclic tetracycline system.

Tetracyclines act bacteriostatically: they inhibit the biosynthesis of microbial cell proteins in ribosomes. Most active against multiplying bacteria. They have a wide spectrum of action, which extends to gram-positive and gram-negative cocci and sticks. Tetracyclines are effective against staphylococci, streptococci, pneumococci and actinomycetes, as well as against spirochetes, rickettsia, chlamydia and protozoa. Proteus, Pseudomonas aeruginosa, mycobacteria, viruses and fungi do not act.

Tetracyclines are the drugs of choice for severe infections: brucellosis, cholera, plague, typhus and typhoid fever. Effective for pneumonia caused by mycoplasmas, chlamydial infections, gonorrhea, syphilis, leptospirosis, amoebic dysentery, rickettsioses, etc.

Tetracyclines well penetrate many tissue barriers, including the placental. Certain amounts pass through the blood-brain barrier. Tetracyclines are excreted in urine and bile, some of them are reabsorbed from the intestines.

Tetracyclines form sparingly soluble non-absorbable complexes with metal ions, while their antimicrobial activity decreases. Therefore, you should not simultaneously take tetracyclines orally with dairy products, antacids, iron medicines and other metals.

Tetracyclines often cause unwanted side effects and complications:

The irritating effect when taking drugs inside is one of the main causes of dyspeptic phenomena (nausea, vomiting, diarrhea), glossitis, stomatitis and other disorders in the mucous membrane of the digestive canal;

They have a toxic effect on the liver, kidneys, blood system;

Capable of causing photosensitivity and associated dermatitis;

They are deposited in tissues rich in calcium (bone, tooth enamel, bind with calcium ions, while the structure of the skeleton is disrupted, staining occurs (in yellow) and damage to teeth;

Oppress intestinal microflora and contribute to the development of candidiasis, superinfection (staphylococcal enteritis). For the prevention and treatment of candidiasis, tetracyclines are combined with the antifungal antibiotic nystatin.

The use of tetracyclines is contraindicated in pregnant and lactating women, children under the age of 12 years. It is prescribed with caution for violations of liver and kidney function, leukopenia, gastrointestinal diseases.

Biosynthetic tetracyclines. Tetracycline hydrochloride is a short-acting antibiotic - 6-8 hours. It is prescribed orally in coated tablets. Tetracycline eye ointment is used to treat local processes - trachoma, blepharitis, bacterial conjunctivitis.

Semi-synthetic tetracyclines. Doxycycline hydrochloride (medomycin, tardox) is well absorbed from the gastrointestinal tract, slowly excreted from the body, therefore, it is prescribed in a lower daily dose, 1-2 times a day.

The drug Unidox solutab is produced in the form of quick-dissolving tablets. The drug contains doxycycline in the form of a monohydrate, so it rarely causes undesirable effects, especially from the gastrointestinal tract, and it can be used from 8 years old.

There are four stereoisomers of natural chloramphenicol, of which only levorotatory, called chloramphenicol, is active against microorganisms.

The mechanism of the antimicrobial action of chloramphenicol is associated with a violation of protein synthesis of microorganisms (bacteriostatic action).

Chloramphenicol (chloramphenicol) has a wide spectrum of action. It covers gram-positive and gram-negative bacteria and cocci, rickettsia, spirochetes, chlamydia. It is not active against anaerobes, Pseudomonas aeruginosa, protozoa, mycobacteria, fungi and viruses. Resistance of microorganisms to it develops relatively slowly. Chloramphenicol is absorbed well from the gastrointestinal tract. Penetrates into all tissues, including passes through the blood-brain barrier and the placenta. In the liver, it undergoes chemical transformations and is excreted by the kidneys in the form of metabolites.

The main indications for its use are typhoid fever, paratyphoid fever, intestinal infections, rickettsioses, brucellosis and other infections.

Known undesirable side effects include:

Severe inhibition of hematopoiesis up to aplastic anemia with a fatal outcome; therefore, the use of chloramphenicol requires regular monitoring of the blood picture;

Irritation of the mucous membranes of the digestive tract (nausea, vomiting);

Oppression of normal intestinal flora, dysbiosis, candidiasis;

Allergic reactions in the form of skin rashes, dermatitis, fever, etc.

Contraindications: oppression of hematopoiesis, liver disease, pregnancy, childhood.

Chloramphenicol should not be prescribed for more than 2 weeks, simultaneously with drugs that inhibit hematopoiesis (sulfonamides, pyrosolones, etc.)

Levomycetin (chloramphenicol) is obtained from the culture liquid and synthetically. It has a very bitter taste, which makes it difficult to use it internally in tablets.

Sintomycin is used locally - a synthetic racemate of chloramphenicol in the form of liniment, suppositories. Levomycetin is available in eye drops, is a part of the combined ointments "Iruksol", "Levomekol", "Mekol borimed" for the treatment of wounds, burns, vaginal suppositories "Levometrin", ear drops "Otidep".

Aminoglycosides in their structure contain amino sugars associated with aglycone, i.e. have a glycosidic structure. They have a bacteriostatic and bactericidal type of action depending on the dose, their mechanism of antimicrobial action is to disrupt the synthesis of proteins in the ribosomes of a microbial cell.

They are antibiotics of a wide spectrum of action: they are effective against a number of gram-positive (staphylococci, pneumococci, etc.) and gram-negative (Escherichia coli, Proteus, Salmonella, etc.) microorganisms. Highly active against acid-fast bacteria, incl. Mycobacterium tuberculosis, Pseudomonas aeruginosa, protozoa. Does not affect fungi, viruses, rickettsia, anaerobes. The resistance of pathogens develops slowly, but cross-resistance to all drugs in this group is possible.

Oral administration of aminoglycosides is not absorbed from the intestine, therefore they are injected. They can be prescribed topically for skin and eye diseases. They penetrate poorly into cells and are effective only with the extracellular location of pathogens. Excreted by the kidneys, creating high concentrations in the urine.

Aminoglycosides are toxic antibiotics. The main specific adverse effects are damage to the auditory nerves (ototoxic effects up to deafness) and kidney damage (nephrotoxic effects). The severity of these undesirable effects depends on the dose. Aminoglycosides can interfere with neuromuscular conduction, which can cause respiratory depression. When treating with aminoglycosides, urine examination and audiometry should be performed at least 1 time per week. Allergic reactions are also noted.

Aminoglycosides are contraindicated in kidney disease, impaired liver function and auditory nerve. They should not be administered in conjunction with diuretics.

Three generations of aminoglycosides are distinguished depending on the opening time, spectrum of action and other characteristics.

Aminogl and cozyds of the 1st generation are more effective against mycobacterium tuberculosis, causative agents of intestinal infections.

Streptomycin sulfate is a waste product of radiant fungi. Has a wide range of antimicrobial activity. They are used mainly in the treatment of tuberculosis, rarely - plague, tularemia, infections of the urinary tract, respiratory organs. The drug is injected most often into the muscle 1-2 times a day, as well as into the body cavity.

Kanamycin sulfate is similar in properties to streptomycin, but is more toxic. Assign 2 times a day to the muscle.

Neomycin sulfate, unlike streptomycin and kanamycin, is inactive against mycobacterium tuberculosis. More toxic. Not used parenterally. It is used topically in the form of an ointment to treat infected wounds and burns. It is part of the combined ointment "Neodex", "Baneocin", "Neoderm", vaginal tablets "Terzhinan", "Sikozhinaks", etc.

Aminogl and cozyds of the 2nd generation have the greatest activity against Pseudomonas aeruginosa, Proteus, Escherichia coli and some staphylococci.

Gentamicin sulfate has a bactericidal effect on gram-negative microorganisms. It is used for urinary tract infections, sepsis, wound infections, burns, etc. It is prescribed 2 times a day. It is used in injections, eye drops, hydrogel plates. It is part of the combined eye drops "Gentadex".

Tobramycin sulfate is highly active against Pseudomonas aeruginosa. Indications for use are similar to those for gentamicin. Produced eye drops Tobrex, Tobrom, is a part of the combined eye drops "Tobradex", "Dexatobrom" with glucocorticoids.

Aminogl and cozyds of the 3rd generation have a wider spectrum of antimicrobial action, including aerobic gram-negative bacteria (Pseudomonas aeruginosa, Proteus, E. coli, etc.), and mycobacterium tuberculosis. Most gram-positive anaerobic bacteria are not affected.

Amikacin sulfate is a semi-synthetic derivative of kanamycin. It is a highly active drug. Prescribed for bacterial infections of severe course: peritonitis, sepsis, meningitis, osteomyelitis, pneumonia, lung abscess, tuberculosis, purulent infections of the skin and soft tissues, etc. The frequency of injections is 2 times a day.

Framycetin (framinazin, isofra) has a bactericidal effect. Active against gram-positive and gram-negative bacteria that cause upper respiratory tract infections. Available as a nasal spray.

Macrolides and azalides

This group includes antibiotics, the structure of which includes a macrocyclic lactone ring. Biosynthetic macrolides are a waste product of radiant fungi; recently, semisynthetic drugs have also been obtained. The mechanism of the antimicrobial action of macrolides is associated with inhibition of the synthesis of proteins of the microbial cell.

In terms of the spectrum of antimicrobial action, macrolides resemble benzylpenicillins: they are active mainly against gram-positive microorganisms. Unlike penicillins, macrolides are active against rickettsia, chlamydia, anaerobes, etc. Those microorganisms that have developed resistance to penicillins, cephalosporins, tetracyclines are sensitive to macrolides. They are used as reserve antibiotics for penicillin intolerance, especially for infections caused by streptococci, pneumococci and clostridia.

Sufficiently absorbed when administered through the mouth, it penetrates well into all tissues. They do not pass through the blood-brain barrier and the placenta. Excreted in the bile, partly in the urine.

Used to treat pneumonia, tonsillitis, tonsillitis, scarlet fever, diphtheria, whooping cough, erysipelas, trophic ulcers, urinary and biliary tract infections, etc. There are children's dosage forms.

Macrolides are fairly safe antimicrobial agents. Undesirable side effects are relatively rare: diarrhea, allergic reactions, liver damage with prolonged use. Contraindicated in case of increased individual sensitivity, liver disease.

Biosynthetic macrolides. Erythromycin is an active antibiotic. It is prescribed internally and locally for the treatment of burns, bedsores in ointments and solutions. In the acidic environment of the stomach, erythromycin is partially destroyed, therefore it should be used in capsules or tablets coated with a membrane that ensures the release of drugs only in the small intestine. Reception interval - 6 hours. It is part of the suspension for the treatment of acne "Zinerit".

Midecamycin (Macropen, Pharmapen) is a natural second generation macrolide. Possesses a wide spectrum of action. Assign 3 times a day.

Spiramycin (doramycin, rovamycin) is used for infectious and inflammatory diseases of the upper respiratory tract, respiratory tract, gynecological diseases 2-3 times a day.

Josamycin (Vilprafen) is used for pneumonia, tonsillitis, skin and soft tissue infections 2 times a day.

Semi-synthetic macrolides with a broader spectrum of action. Effective in the treatment of sexually transmitted infections, staphylococcal infections of the skin and soft tissues, infectious diseases of the gastrointestinal tract caused by atypical bacteria - chlamydia, legionella, mycoplasma. Show anti-inflammatory effect.

Roxithromycin (Rulid, Rulox, Rulicin) are effective semi-synthetic macrolides. Rapidly absorbed when taken orally, accumulates in the tissues of the respiratory tract, kidneys, liver. It is prescribed for infections of the respiratory tract, skin, soft tissues, infections of the genitourinary system 2 times a day.

Clarithromycin (klacid, clarbact, fromilid, clarilide) is 2-4 times more active than erythromycin against staphylococci and streptococci. Effective against Helicobacter pylori... Well absorbed from the gastrointestinal tract, excreted by the kidneys. Prescribed 2 times a day for infections of the respiratory tract, skin, soft tissues, peptic ulcer stomach, etc.

Azithromycin (sumamed, sumalek, azikar, azilid, ziromin, sumamox) is a broad-spectrum antibiotic. Is the first representative new group macrolide antibiotics - azalides. In high concentrations in the focus of inflammation, it has a bactericidal effect. Applied for infections of the respiratory tract, ENT organs, skin, soft tissues, gonorrhea, etc. Prescribed 1 time per day. Undesirable effects are extremely rare.

The drug Zetamax is produced in the form of a sustained-release suspension, which, after a single dose, lasts up to 7 days.

Lincosamides are divided into biosynthetic and semi-synthetic.

Biosynthetic lincosamides. Lincomycin hydrochloride (lincocin) in therapeutic doses acts on a microbial cell bacteriostatically; at higher concentrations, a bactericidal effect may be observed. Suppresses protein synthesis in the microbial cell.

It is active against gram-positive microorganisms: aerobic cocci (staphylococci, streptococci, pneumococci), anaerobic bacteria. Resistance of microorganisms to lincomycin develops slowly. Refers to reserve antibiotics prescribed for infections caused by gram-positive microorganisms resistant to penicillin and other antibiotics.

It is well absorbed when administered through the mouth, penetrates into all tissues, accumulates in bone tissue... Excreted by the kidneys and bile.

It is used for sepsis, osteomyelitis, pneumonia, lung abscess, purulent and wound infections, locally for purulent-inflammatory diseases in the form of ointments, absorbable films (Linkocel, Ferantzel).

Undesirable side effects: dyspeptic symptoms, stomatitis, pseudomembranous colitis, hematopoiesis disorders; at fast intravenous administration- lowering blood pressure, dizziness, weakness.

Contraindications: impaired renal function, liver function, pregnancy.

Semi-synthetic lincosamides. Clindamycin (klimycin, dalacin, vagicin) is a semi-synthetic derivative of lincomycin, similar to it in the spectrum of antimicrobial action, but more active - 2-10 times. Better absorbed from the intestines. It is prescribed internally, parenterally and topically (creams, gels, vaginal suppositories).

Linezolid (Zyvox) disrupts protein synthesis by binding to ribosomes in the microbial cell. Spectrum of action: gram-positive microorganisms (staphylococci, enterococci), gram-negative microorganisms: haemophilus influenzae, legionella, gonococcus, anaerobes. It is well absorbed from the gastrointestinal tract, creates high concentrations in many organs and tissues. Penetrates the BBB. It is excreted through the kidneys. It is used by injection for pneumonia, skin and soft tissue infections.

Undesirable effects: nausea, vomiting, diarrhea, taste changes, anemia, headache.

Rifampicin is a semi-synthetic derivative of rifamycin. It is a broad-spectrum antibiotic. It has a bacteriostatic, and in large doses - a bactericidal effect. It is highly active against mycobacterium tuberculosis, is an anti-tuberculosis drug of the 1st line. Active against a large number gram-positive and gram-negative bacteria (cocci, anthrax sticks, clostridia, brucella, salmonella, proteus, etc.) Resistance to drugs develops rapidly.

The main indications for the use of drugs are tuberculosis of the lungs and other organs. It can be used for infections of the respiratory tract, urinary and biliary tract, osteomyelitis, gonorrhea, meningitis.

Undesirable side effects: liver dysfunction, allergic reactions, dyspeptic symptoms, kidney problems, leukopenia.

Contraindications: hepatitis, impaired renal function, pregnancy, lactation, infants.

Rifamycin (otofa) is active against most microorganisms that cause inflammatory diseases ear. They are used for otitis media in the form of drops.

Rifaximin (alpha normix) is an antibiotic with a broad spectrum of antimicrobial activity, including most gram-positive and gram-negative, aerobic and anaerobic bacteria that cause gastrointestinal infections. Used for gastrointestinal infections.

Antibiotics of different groups

Fusidin sodium is a derivative of fusidic acid. An antibiotic with a narrow spectrum of action, mainly affects gram-positive bacteria: staphylococci, meningococci, gonococci, less active against pneumococci and streptococci. Does not affect gram-negative bacteria, fungi and protozoa. Acts bacteriostatically. Well absorbed when taken enterally. Penetrates into all tissues, accumulates in bone tissue. It is used for staphylococcal infections, especially for osteomyelitis.

Undesirable side effects: dyspeptic symptoms, skin rashes, jaundice.

Fusafungin (bioparox) is an antibiotic for topical use. Possesses a wide spectrum of antibacterial action. Has anti-inflammatory effect. It is prescribed by inhalation for diseases of the upper respiratory tract (sinusitis, pharyngitis, tonsillitis, laryngitis, tracheitis).

Fosfomycin (monural) is a phosphonic acid derivative. It has a broad spectrum of action and a bactericidal type of action (suppresses the synthesis of the bacterial cell wall). Reduces the adhesion of a number of bacteria to the epithelium of the urinary tract. It is used for urinary tract infections: cystitis, urethritis. Available in granules for oral administration.

1.Rational antibiotic therapy. Side effects of antibiotics on the human body and on microorganisms. Formation of antibiotic-resistant and antibiotic-dependent forms of bacteria.

Rational a \ btherapy. - is aimed at preventing resistant forms, therapeutic concentration. The minimum inhibitory concentration / or min inhibitory conc. Is the min conc. A / b, which inhibits the growth of bact. The terminal end is 2-4 r more. Control measures are aimed at obtaining resistant species: 1) new gr or chemical modification of a / b 2) cannot be used as preservatives 3) obtaining a / b, which suppress adhesion and enzymes of the bacterial cell 4) targeted a / b therapy - determines the sensitivity of the strain to a / b and treat those to which the most sensitive 5) cannot be used in medicine, in veterinary medicine 6) is prohibited for prophylaxis.

Side effects of antibiotics.

Formation atypical forms microbes;

Formation of antibiotic-resistant and antibiotic-dependent forms of microorganisms.

2. Reaction of precipitation and its varieties. The mechanism and methods of setting, practical application.

Precipitation reaction and its variants. The essence of this reaction consists in the precipitation (precinitization) of an antigen, which is in a dispersed colloidal state, by the action of specific antibodies in an electrolyte solution. The mechanisms of agglutination and precipitation reactions are similar and are described by the "lattice" theory.

The precipitation reaction is a highly sensitive test, as it detects small amounts of antigen or hapten. The high sensitivity of the precipitation reaction allows it to be used to detect antigens using known anti-sera. In one embodiment, serial dilutions of the antigen are layered on a standard dilution of the diagnostic serum in test tubes, and a precipitate forms in the form of a ring at the border of the two media (ring precipitation). The reaction is assessed by the maximum dilution of the antigen, at which the precipitation ring is visually observed. In addition, turbidity can be recorded by instrumental methods - nephelometry, etc. The precipitation reaction is used in laboratory practice in the diagnosis of infectious diseases, as well as in forensic medical examination to determine the species of proteins, in particular blood stain proteins, sperm, using this reaction in sanitary practice determine the falsification of fish and meat products. In biology, the precipitation reaction is used to form the degree of silt phylogenetic relationship different types animals and plants.

Immunodiffusion. the interaction of antigen with antibodies does not occur in a liquid, but in a gel

IMM noelectrophoresis (IEF) is an immunodifusion gel electrophoresis.

Immunobloting is one of the modern high-precision electrophoresis options - with the analysis of separated proteins by an immunological method.

Coombs reaction (antiglobulin test.). Incomplete antibodies, unlike normal antibodies, are monovalent, since they have one active center, capable of interacting with only one epitope: while the other epitopes remain unbound. As a result, there is no formation of large complexes that precipitate in the electrolyte solution. The latter appear only in reactions with bivalent antibodies. To correct this situation, antiglobulin serum (AGS) is introduced, containing bivalent antibodies to globulin, which will bind monovalent antibodies contained in the test material. antibodies. For example, in the case of pregnancy of a Rh-negative woman, Rh-positive

the fetus will develop incomplete antibodies in her blood serum. To identify them, Rh-positive erythrocytes are introduced into a test tube with the blood serum under study, and then AGS. The appearance of hemagglutination indicates a positive reaction.

3. Staphylococci, classification, characteristics of biological properties. Toxins, pathogenic enzymes. Diseases caused by staphylococci. Pathogenesis, epidemiology, role of staphylococci in hospital infections. Methods for microbiological diagnostics of staphylococcal infection, specific prevention and therapy.

Staphylococcus genus. to this. micrococcea. form a capsule. The electoral medium is milk-salt agar. Colonies are smooth, shiny, odorless, raised above the agar. Differential diagnostics mean - with add. salt. All Gr + cocci arranged in clusters. Optional anaerobes, on ordinary nutrient media form a pigment: white, golden, lim-yellow. grow well on pit Wed, contains Nacl, break down many carbohydrates. Pathogenic factors: capsule, leukocidin, hemolysin, protein A, enterotoxin, fibrinolysin (dissolves fibrin, which limits the local inflammation focus), plasma coagulase (blood plasma clotting), hyaluronidase (promotes the proliferation of staph. -ty) lecithinase (destroying lecithin in the cell membrane of leukocytes), DNase-has golden 1) f-r colonization: f-t lipase - fat to - you, promotes accumulation. 2) f-r invasion-hyaluronidase, fibrinolysin, plasma coagulase 3) the fact of protection against phagocytosis: microcapsule, peptidoglycan, teichoic to-you, protein A 4) antilysozyme activity 5) fact, damage to cells and mc: hemotoxin = hemolysin. enterotoxins A, B, C, D, E- accumulation in food and food poisoning (food toxicosis) 6) ph-r protection against antimicrobial drugs: beta-lactamase f-t Epidemias: Found on the skin and mucus.Gold reservoir ... Staf. there are healthy carriers and patients. Naib. danger is presented. bacteria carriers and patients with skin lesions. Staf. resistant to conv. Wed. meningitis and sepsis. Imm-t after info-ii short-lived, local. Diagnosis: 1) the material (pus) was examined. b / s research and sown on pit. cf. 2) b / l: research material blood, sputum, feces. After the isolation of pure culture. def. species. belong. For staph aureus-plasmacoagulase, hemolysin and protein A. Phage typing to establish the source of information. It is also necessary to determine the sensitivity to a number of a / b. 3) serol is rare Prof-ka: fight against the source of information, prevention of illness in the LU. Treatment: a / b (c-lactam drugs), cephalosporins, less often tetracyclines

Antibiotics (from ancient Greek ἀντί - against + βίος - life) are substances of natural or semi-synthetic origin that suppress the growth of living cells, most often prokaryotic or protozoa.

According to GOST (ST SEV)

Antibiotic - a substance of a microbial, animal or vegetable origin capable of inhibiting the growth of microorganisms or causing their death.

Antibiotics of natural origin are most often produced by actinomycetes, less often by non-mycelial bacteria.

Some antibiotics have a strong suppressive effect on the growth and reproduction of bacteria and at the same time relatively little or no damage to the cells of the macroorganism, and therefore are used as medicines.

Some antibiotics are used as cytostatic (antineoplastic) drugs in the treatment of cancer.

Antibiotics do not affect viruses and therefore are useless in the treatment of diseases caused by viruses (for example, influenza, hepatitis A, B, C, chicken pox, herpes, rubella, measles).

Terminology

Fully synthetic drugs that do not have natural analogues and have a suppressive effect on the growth of bacteria similar to antibiotics have traditionally been called not antibiotics, but antibacterial chemotherapy drugs. In particular, when only sulfonamides were known from antibacterial chemotherapy drugs, it was customary to speak of the whole class of antibacterial drugs as "antibiotics and sulfonamides". However, in recent decades, in connection with the invention of many very strong antibacterial chemotherapy drugs, in particular fluoroquinolones, approaching or exceeding the activity of "traditional" antibiotics, the concept of "antibiotic" began to blur and expand and is now often used not only in relation to natural and semi-synthetic compounds, but also to many strong antibacterial chemotherapy drugs.

History

Main article: Invention of antibiotics

The invention of antibiotics can be called a revolution in medicine. The first antibiotics were penicillin and streptomycin.

Classification

The huge variety of antibiotics and the types of their effects on the human body was the reason for the classification and division of antibiotics into groups. By the nature of the effect on the bacterial cell, antibiotics can be divided into two groups:

• bacteriostatic (bacteria are alive, but not able to multiply),
• bactericidal (bacteria die and then are removed from the body).

The classification by chemical structure, which is widely used in the medical environment, consists of the following groups:

• Beta-lactam antibiotics, divided into two subgroups:
  • Penicillins - Produced by colonies of the mold Penicillinum;
  • Cephalosporins - have a similar structure to penicillins. Used against penicillin-resistant bacteria.

• Macrolides are antibiotics with a complex cyclic structure. The action is bacteriostatic.

• Chloramphenicol - Use is limited due to the increased risk of serious complications - damage to the bone marrow, which produces blood cells. The action is bacteriostatic.

• Glycopeptide antibiotics disrupt the synthesis of the bacterial cell wall. They have a bactericidal effect, however, against enterococci, some streptococci and staphylococci, they act bacteriostatically.

• Lincosamides have a bacteriostatic effect, which is due to the inhibition of protein synthesis by ribosomes. In high concentrations, against highly sensitive microorganisms, they can exhibit a bactericidal effect.

• Antibiotics of different groups - Rifamycin, Ristomycin sulfate, Fusidin sodium, Polymyxin M sulfate, Polymyxin B sulfate, Gramicidin, Heliomycin.

• Antifungal drugs - destroy the membrane of fungal cells and cause their death. The action is lytic. They are gradually being replaced by highly effective synthetic antifungal drugs.

• Antileprotic drugs - Diaphenylsulfone, Solusulfone, Diucifon.

Beta-lactam antibiotics

Main article: Beta-lactam antibiotics

Beta-lactam antibiotics (β-lactam antibiotics, β-lactams) are a group of antibiotics that are united by the presence of a β-lactam ring in the structure. Beta-lactams include subgroups of penicillins, cephalosporins, carbapenems, and monobactams. The similarity of the chemical structure predetermines the same mechanism of action of all β-lactams (violation of the synthesis of the bacterial cell wall), as well as cross-allergy to them in some patients.

Penicillins

Main article: Penicillins

Penicillins are antimicrobial drugs belonging to the class of β-lactam antibiotics. The ancestor of penicillins is benzylpenicillin (penicillin G, or simply penicillin), which has been used in clinical practice since the early 1940s.

Cephalosporins

Main article: Cephalosporins

"Cephalosporins" are a class of β-lactam antibiotics, the chemical structure of which is based on 7-aminocephalosporic acid (7-ACA). The main features of cephalosporins in comparison with penicillins are their greater resistance to β-lactamases - enzymes As it turned out, the first antibiotics - cephalosporins, having high antibacterial activity, do not possess complete resistance to β-lactamases.Being resistant to plasmid lactamases, they are destroyed by chromosomal lactamases, which are produced by gram-negative bacteria. antimicrobial action, improving pharmacokinetic parameters, numerous semisynthetic derivatives have been synthesized.

Carbapenems

Main article: Carbapenems

Carbapenems (eng. Carbapenems) - a class of β-lactam antibiotics, with a wide range of actions, having a structure that determines their high resistance to beta-lactamases. Not resistant to the new type of beta-lactamase NDM1.

Macrolides

Main article: Macrolides

Macrolides are a group of drugs, mostly antibiotics, whose chemical structure is based on a macrocyclic 14- or 16-membered lactone ring, to which one or more carbohydrate residues are attached. Macrolides belong to the class of polyketides, compounds of natural origin. Macrolides are among the least toxic antibiotics.

Also referred to as macrolides:

• azalides, which are a 15-membered macrocyclic structure obtained by including a nitrogen atom in a 14-membered lactone ring between 9 and 10 carbon atoms;
• ketolides are 14-membered macrolides in which a keto group is attached to the lactone ring at the 3 carbon atom.

In addition, the macrolide group nominally includes the immunosuppressive drug tacrolimus, the chemical structure of which is a 23-membered lactone ring.

Tetracyclines

Main article: Tetracyclines

Tetracyclines are a group of antibiotics belonging to the class of polyketides, which are similar in chemical structure and biological properties. Representatives of this family are characterized by a common spectrum and mechanism of antimicrobial action, complete cross-resistance, and similar pharmacological characteristics. Differences concern some physical and chemical properties, the degree of antibacterial effect, characteristics of absorption, distribution, metabolism in the macroorganism and tolerance.

Aminoglycosides

Main article: Aminoglycosides

Aminoglycosides are a group of antibiotics, the common chemical structure of which is the presence in the molecule of an amino sugar linked by a glycosidic bond to an aminocyclic ring. In terms of chemical structure, spectinomycin, an aminocyclitol antibiotic, is also close to aminoglycosides. The main clinical significance of aminoglycosides is their activity against aerobic gram-negative bacteria.

Lincosamides

Main article: Lincosamides

Lincosamides (syn.: Lincosamides) are a group of antibiotics that includes the natural antibiotic lincomycin and its semisynthetic analogue clindamycin. Possess bacteriostatic or bactericidal properties, depending on the concentration in the body and the sensitivity of microorganisms. The action is due to the suppression of protein synthesis in bacterial cells by binding of the 30S-subunit of the ribosomal membrane. Lincosamides are resistant to action of hydrochloric acid gastric juice. After oral administration, they are rapidly absorbed. It is used for infections caused by gram-positive cocci (mainly as second-line drugs) and non-spore-forming anaerobic flora. They are usually combined with antibiotics that affect gram-negative flora (for example, aminoglycosides).

Chloramphenicol

Main article: Chloramphenicol

Chloramphenicol (chloramphenicol) is a broad-spectrum antibiotic. Colorless crystals of very bitter taste. Chloramphenicol is the first synthetic antibiotic. Used to treat typhoid fever, dysentery and other diseases. Toxic. CAS Registration Number :. The racemic form is syntomycin.

Glycopeptide antibiotics

Main article: Glycopeptide antibiotics

Glycopeptide antibiotics - a class of antibiotics, consists of glycosylated cyclic or polycyclic nonribosomal peptides. This class of antibiotics inhibits the synthesis of cell walls in susceptible microorganisms by inhibiting the synthesis of peptidoglycans.

Polymyxins

Main article: Polymyxins

Polymyxins are a group of bactericidal antibiotics with a narrow spectrum of activity against gram-negative flora. The main clinical significance is the activity of polymyxins against P. aeruginosa. By chemical nature these are polyene compounds containing polypeptide residues. In usual doses, drugs of this group act bacteriostatically, in high concentrations they have a bactericidal effect. Of the drugs, polymyxin B and polymyxin M are mainly used. They have pronounced nephrotoxicity and neurotoxicity.

Sulfanilamide antibacterial drugs

Main article: Sulfonamides

Sulfanilamides (Latin sulfanilamide) are a group of chemicals derived from para-aminobenzenesulfonamide - sulfanilic acid amide (para-aminobenzenesulfonic acid). Many of these substances have been used as antibacterial drugs since the mid-twentieth century. para-aminobenzenesulfamide - the simplest compound of the class - is also called white streptocide and is still used in medicine. Sulfanilamide prontosil (red streptocid), which is somewhat more complex in structure, was the first drug in this group and, in general, the first synthetic antibacterial drug in the world.

Quinolones

Main article: Quinolones

Quinolones are a group of antibacterial drugs that also include fluoroquinolones. The first drugs in this group, primarily nalidixic acid, were used for many years only for urinary tract infections. But after receiving fluoroquinolones, it became obvious that they can be of great importance in the treatment of systemic bacterial infections... In recent years, this is the most dynamically developing group of antibiotics.

Fluoroquinolones (English fluoroquinolones) are a group of medicinal substances with pronounced antimicrobial activity, widely used in medicine as broad-spectrum antibiotics. In terms of the breadth of the spectrum of antimicrobial action, activity, and indications for use, they are really close to antibiotics, but differ from them in chemical structure and origin. (Antibiotics are products of natural origin or close synthetic analogues, while fluoroquinolones do not have natural analogue). Fluoroquinolones are subdivided into the first (pefloxacin, ofloxacin, ciprofloxacin, lomefloxacin, norfloxacin) and the second generation (levofloxacin, sparfloxacin, moxifloxacin) drugs. Of the drugs in the fluoroquinolone group, lomefloxacin, ofloxacin, ciprofloxacin, levofloxacin, sparfloxacin and moxifloxacin are included in the List of Vital and Essential Medicines.

Nitrofuran derivatives

Main article: Nitrofurans

Nitrofurans are a group of antibacterial agents. Gram-positive and gram-negative bacteria, as well as chlamydia and some protozoa (Trichomonas, lamblia) are sensitive to nitrofurans. Usually nitrofurans act bacteriostatically on microorganisms, however, in high doses, they can have a bactericidal effect. Microflora resistance rarely develops to nitrofurans.

Anti-tuberculosis drugs

Main article: Anti-TB drugs

Anti-tuberculosis drugs are drugs that are active against Koch's bacillus (lat.Mycobactérium tuberculósis). According to the international anatomical-therapeutic-chemical classification (Russian ATC, English ATC), they have the code J04A.

According to their activity, anti-tuberculosis drugs are divided into three groups:

• the most effective (isoniazid, rifampicin),
• moderately effective (streptomycin, kanamycin, amikacin, ethambutol, pyrazinamide, ofloxacin, ciprofloxacin, ethionamide, prothionamide, capreomycin, cycloserine),
• low effective (PASK, thioacetazone)

Antifungal antibiotics

• Nystatin is a polyene antifungal drug used in the treatment of candidiasis. First isolated from Streptomyces noursei in 1950.
• Amphotericin B is a drug, antifungal drug. Polyene macrocyclic antibiotic with antifungal activity. Produced by Streptomyces nodosus. It has a fungicidal or fungistatic effect depending on the concentration in biological fluids and on the sensitivity of the pathogen. It binds to sterols (ergosterols) located in the cell membrane of the fungus and is incorporated into the membrane, forming a low-selective ion channel with very high conductivity. As a result, the release of intracellular components into the extracellular space and lysis of the fungus occurs. Active against Candida spp., Cryptococcus neoformans, Aspergillus spp. and other mushrooms. Does not act on bacteria, rickettsia, viruses.
• Ketoconazole, trade name Nizoral (active ingredient, according to IUPAC: cis-1-acetyl-4 - methoxy] phenyl] piperazine) is an antifungal drug derived from imidazole. Important features ketoconazole is its effectiveness when taken orally, as well as its effect on both superficial and systemic mycoses. The action of the drug is associated with a violation of the biosynthesis of ergosterol, triglycerides and phospholipids, which are necessary for the formation of the cell membrane of fungi.
• Miconazole is a drug for the local treatment of most fungal diseases, including dermatophytes, yeast and yeast-like, external forms of candidiasis. The fungicidal effect of miconazole is associated with a violation of the synthesis of ergosterol, a component of the fungal cell membrane.
• Fluconazole (Fluconazole, 2- (2,4-difluorophenyl) -1,3-bis (1H-1,2,4-triazol-1-yl) -2-propanol) is a common synthetic drug of the triazole group for treatment and prevention candidiasis and some other mycoses. Antifungal agent, has a highly specific effect, inhibiting the activity of fungal enzymes dependent on cytochrome P450. Blocks the conversion of fungal lanosterol into ergosterol; increases the permeability of the cell membrane, disrupts its growth and replication. Fluconazole, being highly selective for cytochrome P450 of fungi, practically does not inhibit these enzymes in the human body (in comparison with itraconazole, clotrimazole, econazole and ketoconazole, it suppresses oxidative processes in human liver microsomes to a lesser extent, dependent on cytochrome P450).

Nomenclature

For a long time, there were no uniform principles for naming antibiotics. Most often they were called by the generic or specific name of the producer, less often - in accordance with the chemical structure. Some antibiotics are named according to the locality from which the producer was isolated, and, for example, etamycin got its name from the strain number (8).

In 1965, the International Committee on Antibiotic Nomenclature recommended the following guidelines:

1. If the chemical structure of the antibiotic is known, the name should be chosen taking into account the class of compounds to which it belongs.
2. If the structure is not known, the name is given by the name of the genus, family or order (and if they are used, then the species) to which the producer belongs. The suffix "mycin" is assigned only to antibiotics synthesized by bacteria of the order Actinomycetales.
3. The name can give an indication of the spectrum or mode of action.

Antibiotic action

Antibiotics, unlike antiseptics, have antibacterial activity not only when applied externally, but also in biological media of the body when they are systemically (orally, intramuscularly, intravenously, rectally, vaginally, etc.) used.

Mechanisms of biological action

• Disruption of cell wall synthesis by inhibiting peptidoglycan synthesis (penicillin, cephalosporin, monobactams), the formation of dimers and their transfer to growing peptidoglycan chains (vancomycin, flavomycin) or chitin synthesis (niccomycin, tunicamycin). Antibiotics acting by a similar mechanism have a bactericidal effect, do not kill resting cells and cells devoid of a cell wall (L-form bacteria).
• Disruption of the functioning of membranes: violation of the integrity of the membrane, the formation of ion channels, the binding of ions into complexes, soluble in lipids, and their transportation. Nystatin, gramicidins, polymyxins act in a similar way.
• Suppression of the synthesis of nucleic acids: binding to DNA and hindering the advancement of RNA polymerase (acttidine), stitching of DNA strands, which makes it impossible to unwind (rubomycin), inhibition of enzymes.
• Violation of the synthesis of purines and pyrimidines (azaserine, sarcomycin).
• Violation of protein synthesis: inhibition of activation and transfer of amino acids, functions of ribosomes (streptomycin, tetracycline, puromycin).
• Inhibition of the work of respiratory enzymes (antimycins, oligomycins, aurovertin).

Interaction with alcohol

Alcohol can affect both activity and metabolism of antibiotics by affecting the activity of liver enzymes that break down antibiotics. In particular, some antibiotics, including metronidazole, tinidazole, chloramphenicol, co-trimoxazole, cefamandol, ketoconazole, latamoxef, cefoperazone, cefmenoxime, and furazolidone, chemically interact with alcohol, leading to serious side effects including vomiting, nausea, and convulsions death. Drinking alcohol with these antibiotics is categorically contraindicated. In addition, the concentration of doxycycline and erythromycin can, under certain circumstances, be significantly reduced with alcohol consumption.

Antibiotic resistance

Main article: Antibiotic resistance

Antibiotic resistance is understood as the ability of a microorganism to resist the action of an antibiotic.

Antibiotic resistance arises spontaneously as a result of mutations and becomes fixed in the population under the influence of an antibiotic. The antibiotic alone is not the cause of the emergence of resistance.

Mechanisms of resistance

• The microorganism may lack a structure on which the antibiotic acts (for example, bacteria of the genus Mycoplasma (Latin Mycoplasma) are insensitive to penicillin, since they do not have a cell wall);
• The microorganism is impermeable to the antibiotic (most gram-negative bacteria are immune to penicillin G, since the cell wall is protected by an additional membrane);
• The microorganism is able to convert the antibiotic into an inactive form (many staphylococci (Latin Staphylococcus) contain the β-lactamase enzyme, which destroys the β-lactam ring of most penicillins)
• Due to gene mutations, the metabolism of the microorganism can be changed in such a way that the reactions blocked by the antibiotic are no longer critical for the vital activity of the organism;
• The microorganism is able to pump the antibiotic out of the cell [source unspecified 412 days].

Application

Antibiotics are used to prevent and treat inflammation caused by bacterial flora. According to the effect on bacterial organisms, bactericidal (killing bacteria, for example, by destroying their outer membrane) and bacteriostatic (inhibiting the reproduction of a microorganism) antibiotics are distinguished.

Other areas of application

Some antibiotics also have additional valuable properties not related to their antibacterial activity, but related to their effect on the macroorganism.

Antibiotics: original and generic

Main article: Generic

In 2000, a review was published, which provides data on a comparative analysis of the quality of the original antibacterial drug and 40 of its generics from 13 different countries. 28 generics have the amount released upon dissolution active substance was significantly lower than the original, although they all had the appropriate specification. In 24 out of 40 drugs, the recommended 3% limit of impurities and the threshold (> 0.8%) of 6,11-di-O-methyl-erythromycin A, a compound responsible for the occurrence of undesirable reactions, were exceeded.

The study pharmaceutical properties generics of azithromycin, the most popular in Russia, also showed that the total amount of impurities in copies is 3.1-5.2 times higher than that in the original drug Sumamed (manufactured by Teva Pharmaceutical Industries), including unknown impurities - 2– 3.4 times.

It is important that a change in the pharmaceutical properties of a generic drug reduces its bioavailability and, therefore, ultimately leads to a change in the specific antibacterial activity, a decrease in tissue concentration and a weakening of the therapeutic effect. So, in the case of azithromycin, one of the copies at an acidic pH value (1.2) in the solubility test simulating the peak of gastric juice separation was dissolved only by 1/3, and the other - too early, at the 10th minute, which would not allow the drug is completely absorbed in the intestine. And one of the generics of azithromycin lost its ability to dissolve at a pH value of 4.5.

The role of antibiotics in natural microbiocenoses

It is not clear how great is the role of antibiotics in the competitive relationship between microorganisms in vivo. Zelman Waxman believed that this role is minimal, antibiotics are not formed otherwise than in pure cultures on rich media. Subsequently, however, it was found that in many producers the activity of antibiotic synthesis increases in the presence of other species or specific products of their metabolism. In 1978, LM Polyanskaya, using the example of S. olivocinereus heliomycin, which has a glow when exposed to UV radiation, showed the possibility of the synthesis of antibiotics in soils. Presumably, antibiotics are especially important in competition for environmental resources for slow-growing actinomycetes. It was experimentally shown that when actinomycete cultures are introduced into the soil, the population density of the actinomycete species exposed to the action of the antagonist decreases faster and stabilizes at a lower level than other populations.

According to a 2011 poll by the Russian Public Opinion Research Center (VTsIOM), 46% of Russians believe antibiotics kill viruses as well as bacteria.

see also

• Antiseptics
• Probiotics
• Dysbacteriosis
• Antibiotic resistance

Notes (edit)

• Molecular Pharmacology, Vol 11, 166-173, 1975 Antibiotics as Tools for Metabolic Studies XVIII. Inhibition of Sodium- and Potassium-Dependent Adenosine Triphosphatase JOHN B. SUSA, HENRY A. LARDY

Antibiotics are. What are Antibiotics?

substances formed by microorganisms, higher plants or tissues of animal organisms, as well as semi-synthetic and synthetic analogs of these substances, selectively suppressing the development of microorganisms or cells of malignant tumors.

The emergence of the doctrine of A. is associated with the discovery in 1929 by the English researcher A. Fleming of the antimicrobial action of the mold Penicillium, the active principle of which was called penicillin. In a purified form, penicillin was obtained in Great Britain in 1940 by N.W. Florey, E.V. Chain and independently in the USSR in 1942 by Z.V. Ermolyeva and T.I. Balezina. The development of methods for biological synthesis, isolation and purification of penicillin, the creation of its dosage forms provided an opportunity medical use antibiotics.

More than 6 thousand natural A. have been described, many tens of thousands of semi-synthetic derivatives. Of the greatest practical importance are about 50 antibiotics produced in various dosage forms.

Distinguish A. narrow spectrum of antimicrobial action, active mainly against gram-positive (natural or some semi-synthetic Penicillins, Macrolides, fusidin, lincomycin, etc.) or gram-negative (polymyxins) microorganisms; a wide spectrum, active against both gram-positive and gram-negative microorganisms (tetracyclines, aminoglycosides, chloramphenicol, some semi-synthetic penicillins, cephalosporins, rifampicin); anti-tuberculosis (streptomycin, kanamycin, rifampicin, florimycin, cycloserine); antifungal (nystatin, amphotericin B, griseofulvin, etc.); acting on protozoa (monomycin); antitumor (actinomycins, anthracyclines, bleomycins, etc.). In addition, A., acting on helminths (hygromycin B), as well as A., possessing the properties of immunosuppressants, for example, cyclosporin A, have been obtained (see Immunocorrective agents). According to the main mechanisms of antimicrobial action, A. is isolated, inhibiting the synthesis of the bacterial cell wall (penicillins, cephalosporins, A. from the vancomycin group); disrupting the functions of ribosomes and the processes of protein synthesis in microbial cells (macrolides, aminoglycosides, tetracyclines, chloramphenicol, lincomycin); changing the permeability of the cytoplasmic membrane of microorganisms and having a detergent effect on them (polymyxins, nystatin, levorin, amphotericin B, etc.); disrupting the synthesis of RNA of bacteria (rifampicin). The mechanisms of action of antitumor A are mainly due to a violation of the metabolism of DNA and RNA of tumor cells. By the nature of the antimicrobial action, A. is divided into bactericidal (which quickly cause the death of microbial cells) and bacteriostatic (which inhibit the growth and reproduction of microbial cells). Bactericidal action is possessed mainly by A., inhibiting the synthesis of the cell wall, violating the permeability of the cytoplasmic membrane of microorganisms or blocking the synthesis of RNA in them. For the overwhelming majority of A., which disrupt intracellular protein synthesis and the functions of ribosomes, bacteriostatic action on microorganisms is characteristic. The exception is A. from the group of aminoglycosides, which differ in that they not only disrupt the functions of ribosomes and intracellular protein synthesis, but also, probably, secondarily (indirectly) inhibit the synthesis of the cell wall of microorganisms. The selectivity of the action of A. different groups is not the same. The highest selectivity of action is distinguished by penicillins and cephalosporins. since they interfere with the synthesis of specific proteins of the cell wall of microorganisms and do not affect the synthesis of cell membranes of the macroorganism, in the formation of which protein substrates are involved, which differ significantly from the proteins of microbial cells in chemical structure. Low selectivity is characteristic of antitumor antibiotics, which affect the metabolism of DNA and RNA not only in malignant, but also in normal (especially rapidly proliferating) cells of the body. This is due to the pronounced toxicity of antitumor antibiotics. The effectiveness of antibiotic therapy is determined by several factors. First of all, one should take into account the spectrum of antimicrobial action of A. Since many diseases (for example, typhoid and typhus, syphilis, anthrax, plague, tuberculosis) are caused by certain types of pathogens, in such diseases A. with the corresponding spectra of antimicrobial action is usually prescribed immediately after the establishment of clinical diagnosis, i.e. before isolating and identifying the pathogen. For wound infections, pneumonia, meningitis, urinary tract infections, etc. A.'s choice is advisable to carry out on the basis of the identification of the pathogen (or association of pathogens) and the study of the antibioticogram, which requires a significant investment of time. However, in these diseases, antibiotic therapy should be started as early as possible after the diagnosis is established, therefore, in such cases, any A. of a wide spectrum of action (for example, ampicillin, cephalosporins, kanamycin, tetracyclines) or combinations of these antibiotics (for example, ampicillin with kanamycin). Subsequently (after isolating the pathogens and studying their antibioticogram), if necessary, an appropriate correction of antibiotic therapy is carried out.

To achieve a therapeutic effect, antibiotics with bacteriostatic action are usually used. For severe infections (for example, sepsis, meningococcal infection), and also in infectious diseases in persons with weakened immunity, A. with a bactericidal type of action is used.

In the process of antibiotic therapy, it is important to prescribe the optimal doses and methods of administration of drugs, taking into account their pharmacokinetics in the patient's body. The optimal doses of A. are those at which the concentration of A. in the blood is 2-3 times higher than the value of its minimum suppressive concentration in relation to the isolated pathogen. In patients with concomitant renal failure, when choosing A. and determining their doses, it is necessary to take into account the characteristics of the pharmacokinetics of individual drugs. So, among A. there are drugs (gentamicin, sisomycin, streptomycin, carbenicillin, cephaloridin, cephalexin, etc.), the release of which is significantly reduced when renal failure, which contributes to the enhancement of their toxicity in this pathology. Doses of such A. are reduced in accordance with the degree of impairment of renal excretory function (according to creatinine clearance). Correction of doses of some A. (preparations of benzylpenicillin, ampicillin, oxacillin, lincomycin and cephalothin) is carried out only when creatinine clearance is less than 30 ml / min. The release of erythromycin, doxycycline, chloramphenicol, rifampicin and fusidin from the body in renal failure does not change, therefore, these A. are prescribed in normal doses for violations of renal excretory function. In a severe course of infectious diseases, A. preparations are usually used for parenteral administration. For the treatment of intestinal infections (dysentery, enteritis, etc.), A. preparations are used, intended for oral administration. If necessary, resort to local administration of A., for example, intrapleurally with pleurisy, in abdominal cavity with peritonitis. The effectiveness of antibiotic therapy is largely determined by its optimal duration: A. treatment should be carried out until the therapeutic effect is permanently consolidated. Combinations A. are used to expand the spectrum of action and enhance the antibacterial effect, as well as to reduce the frequency and severity of side effects. Combined antibiotic therapy is indicated mainly in the following cases: at the beginning of treatment with suspicion of a mixed infection (caused by an association of pathogens) and a severe course of the disease; in order to enhance the antibacterial effect (for example, penicillin + streptomycin for septic endocarditis or respiratory diseases caused by hemophilic sticks); to prevent or slow down the formation of resistant forms when prescribing macrolides, fuzidin and other A., ​​characterized by the rapid development of pathogens resistant to their action; in order to reduce the therapeutic doses of A. with toxicity (for example, gentamicin + carbenicillin in the treatment of Pseudomonas aeruginosa infection). When choosing a combination, you should avoid combinations of A. with a bactericidal and bacteriostatic type of action, because bacteriostatic A., as a rule, significantly weaken the antimicrobial effect of bactericidal drugs.

Antibiotic prophylaxis and preventive antibiotic therapy are used for threatening infection before development clinical symptoms diseases and in order to eliminate pathogens (for example, to prevent the development of blennorrhea in newborns, with extensive wounds, in contact with a patient with plague, to prevent bacterial complications of viral infections).

Resistance (resistance) of microorganisms to A. is a complex problem that arises at all stages of chemotherapy for bacterial infections. Distinguish between natural and acquired resistance of microorganisms. Natural resistance is determined by the properties of the species or genus of microorganisms. Acquired resistance is associated with a change in the genome of a microbial cell due to mutations and the selection of resistant variants under the influence of A. There are two types of acquired resistance: by a single-stage mutation (the so-called streptomycin type), when an increase in resistance after contact with A. occurs quickly, and by multi-stage mutations (the so-called penicillin type), when the development of resistance occurs slowly, stepwise. Transmitted (transmissible) resistance is associated with the transfer of genes of resistance to A. (sometimes simultaneously to the A. series - multiple resistance) from one microorganism to another with the help of extrachromosomal genetic elements - plasmids and transposons. The biochemical mechanisms of microorganism resistance to A. are due to A. inactivation due to the action of specific enzymes produced by resistant microorganisms (resistance to penicillins, aminoglycosides), a change in the target of A. action (to tetracyclines, macrolides, etc.), difficulty in A. transport through the cell wall pathogen. Side effects in antibiotic therapy can be divided into 3 main groups: allergic, toxic and associated with the chemotherapeutic effect A. Allergic reactions can occur with the use of most A., however, they differ in nature, severity and outcome; their occurrence is independent of the dose, but they increase with increasing doses. Life-threatening include Anaphylactic shock, laryngeal edema: non-life-threatening - skin itching, urticaria, conjunctivitis, rhinitis, etc. The frequency and severity of allergic reactions during antibiotic therapy are determined mainly by the allergenic properties of A. and the products of their transformation in the body, methods of administration of drugs (allergic reactions occur more often with local and inhalation A.) and individual sensitivity of patients. Allergic reactions are most often observed when prescribing A. from the group of penicillins, especially when using long-acting drugs (bicillins).

Side effects of a toxic nature in antibiotic therapy are associated with the properties and mechanism of action of A. Their severity is due to the dose of the injected drug, the route of administration, its interaction with other drugs, and the patient's condition. The rational use of A. provides for the choice of not only the most active, but also the least toxic drug, as well as its appointment in doses that are harmless to the patient's body. Special care is required for the treatment of newborns and young children, the elderly (due to the peculiarities of the processes of excretion and metabolism, disorders of water and electrolyte metabolism).

Toxic effects are due to the effect of A. on individual organs and tissues. So, neurotoxic complications are associated with damage to the auditory branches of the VIII pair of cranial nerves (when using monomycin, kanamycin, streptomycin, florimycin, ristomycin), the effect on the vestibular apparatus (when prescribing streptomycin, florimycin, kanamycin, neomycin gentamycin). V individual cases with the introduction of some A., other neurotoxic complications are observed (damage to the optic nerve, polyneuritis, headaches, neuromuscular blockade). A. of various groups has a nephrotoxic effect: polymyxins, aminoglycosides, cephalosporins, amphotericin B, griseofulvin, ristomycin, etc. Nephrotoxic reactions often occur in patients with impaired renal excretory function. To prevent nephrotoxic reactions, it is necessary to choose A., the doses and schemes of its use, taking into account the clinical and laboratory data on the state of the excretory function of the kidneys, and the treatment should be carried out under constant control of the concentration of the drug in the urine and blood. Toxic effect A. on the gastrointestinal tract is associated with their local irritating effect on the mucous membranes and is manifested by nausea, vomiting, anorexia, abdominal pain, diarrhea. Inhibition of hematopoiesis (sometimes up to hypo- and aplastic anemia) is observed with the use of chloramphenicol and amphotericin B; hemolytic anemia can occur with the use of chloramphenicol. There are A., mainly with antitumor activity, which have a direct immunosuppressive effect. Along with this, some antibacterial A., for example, erythromycin, have an immunostimulating effect. Manifestations of embryotoxic action can be observed in the treatment of pregnant women with streptomycin, kanamycin, neomycin, tetracycline. In connection with the possible effect on the fetus, the use of toxic A. in the last 3-6 ° weeks. pregnancy is contraindicated. Side effects associated with the antimicrobial effect of A. are expressed in the development of dysbacteriosis and disorders of the formation of specific immunity during antibiotic therapy of bacterial infections (for example, typhoid fever).

The frequency and severity of side effects during antibiotic therapy (based on the analysis of statistical data) does not exceed the same indicators when prescribing other drugs (and sometimes it is much lower). If the basic principles of the rational appointment of A. are observed, it is possible to achieve an optimal effect and minimize side effects.

Bibliography: Lancini D. and Parenti F. Antibiotics, per. from English., M., 1985; S.M. Navashin Contemporary problems antibacterial therapy, Ter. arch., t. 60, no. 8, p. 3, 1988; S.M. Navashin and Fomina I.P. Rational antibiotic therapy, M., 1982; Guide to Infectious Diseases, ed. IN AND. Pokrovsky and K.M. Loban, M., 1986.

substances produced by microorganisms, higher plants or tissues of an animal organism, with the ability to selectively suppress the development of microorganisms or cells of certain tumors.

Antiseptics - a set of measures aimed at destroying infectious agents on the surface of the body (skin, mucous membranes, wounds), cavities.

Disinfection - the destruction of infectious agents in the external environment.

In practical terms, two actions are distinguished: bacteriostatic and bactericidal.

The bacteriostatic effect is to delay the growth of bacteria while the substance continues to act.

The bactericidal effect is expressed in the complete killing of microorganisms.

Often the same substances can, at different concentrations, have both bacteriostatic and bactericidal effects. For a bactericidal action, a higher concentration is required than for a bacteriostatic.

Chemical antiseptics - the destruction of microorganisms in a wound, pathological focus or the patient's body using various chemicals.

The mechanism of action of such antiseptic substances is different: some of them precipitate the protein, of which the cell membranes of bacteria mainly consist; others cause the death of bacteria by penetrating into their cells and affecting their plasma; still others create unfavorable conditions for the growth of bacteria and their reproduction.

Soluble aromatic compounds with an antiseptic effect are typical protoplasmic poisons that, even in weak solutions, inhibit the reproduction of bacteria, and in a stronger concentration kill all microorganisms. Many of them are among the most commonly used antiseptic and disinfectants.

Examples of antiseptics

Salicylic acid (C6H4 (OH) COOH). it is used as a good antiseptic for various rashes (in a 1% solution), corns (10%), as a deodorizing agent in the form of powders for foot sweats (1-2%); in remedies for freckles - as promoting desquamation of the epidermis (up to 1-1.2%), against cracks in the skin (1%).

When mixing solutions of 2 parts of salicylic acid and 1 part of boric acid, a strongly bitter boric-salicylic acid is obtained, which serves as an excellent antiseptic, many times superior in action to boric and salicylic acids taken separately. The combination of salicylic acid with benzyl alcohol (a good preservative) also works very well.

Boric (ortho-boric) acid (H3BO3) is one of the weak acids, but at high temperature acquires the properties of a very strong acid. In a mixture with salicylic acid, it gives a bitter compound (boric-salicylic acid), which has a very strong antiseptic effect, almost equal in strength to carbolic acid.

When boric acid is mixed with fats, its antiseptic properties are reduced to almost zero. In this case, it is much more expedient in this case to use boric-salicylic acid or benzoic acid. Apply 1-5% - aqueous and alcohol-water solutions.

Boric acid solutions are mildly irritating and do not precipitate protein. Boric acid exhibits bacteriostatic action only in 2-4% solutions.

Benzoic acid (C6H5COOH) is used as a strong antiseptic and has a much stronger effect than salicylic acid. Benzoic acid slightly irritates the skin and promotes flaking of the epidermis, so it is used to remove freckles and blemishes. It is soluble in fats and is used for preserving fats used in the preparation of cosmetic creams. Up to 1% is introduced into cosmetic preparations.

Benzyl alcohol (C7H8O) is an energetic antiseptic that is significantly superior to phenol, but devoid of its toxicity. Physiologically flawless. It is used as an antiseptic in creams, lotions, etc. The antiseptic effect of benzyl alcohol is further enhanced by its combination with borosalicylic acid.

Bornosalicylic acid is a strong and harmless antiseptic and preservative agent, which is 10-15 times more effective than phenol, but devoid of its drawbacks, does not irritate and does not smooth the skin.

Glyceroboride (boroglyceride) - is a chemical compound in which 3HO of glycerol is replaced by boric acid when water is released: C3H5 (OH) 3 + H3BO3> C3H5BO3 + 3H2O

Of the compounds of glyceroboride, its sodium and calcium salts are of interest. Both salts are very gentle, non-irritating, non-toxic antiseptics, and are not inferior in strength to phenol.

Naphthalene is a brown oily substance with a weak specific odor. It is obtained from naphthalan oil. It lubricates and softens the skin well. Naftalan ointment is prepared from naftalan.

It has a softening, slightly pain-relieving effect on the skin. It has both bacteriostatic and bactericidal action. Promotes the resorption of infiltrates. It has anti-inflammatory, epithelial and granulating properties.

Method of use: in case of seborrhea of ​​the skin of the face or scalp, it is wiped with cotton wool dipped in naphthalene alcohol, at first every day, and then every other day until a positive result is achieved. This alcohol is equally useful in the treatment of dry scalp seborrhea.

Resorcinol, or metadioxybenzene C6H4 (OH) 2. When rubbed with two parts of camphor or menthol, it gives oily liquids - camphor resorcinol or menthol resorcinol. Like salicylic and carbolic acids, it has strong anti-putrefactive properties, but is less caustic and poisonous. Vigorously coagulates protein and therefore acts on the skin in a corrosive and cauterizing manner, painlessly sloughs off the epidermis.

It is used in the form of 2-5% creams or liquids for acne, against seborrhea of ​​the skin and hair loss, and in a 5-10% solution for freckles.

Timol (C6H3CH3C3H7OH). Therapeutically, thymol is similar to carbolic acid, but the effect is somewhat weaker and milder. It has a pleasant smell and is less toxic. Thymol is a good antiseptic agent, used in dental preparations, to lubricate burns, while acting as a pain reliever.

In the amount of 0.1-0.5%, thymol is included as an integral part in all kinds of dental products, creams, lotions; in soaps, under the influence of free alkali, which is in them and is formed during hydrolysis during washing, thymol is converted into indifferent sodium thymolate.

Thioresorcinol (C6H4O2S2). It combines the action of resorcinol and sulfur, therefore it is of great interest for cosmetics and in dermatological practice.

Formalin is a 40% formaldehyde solution.

Colorless liquid with a pungent odor, easily miscible with water and alcohol in all proportions.

Has tanning and antiseptic properties, especially pronounced in an alkaline environment. Formalin tans the proteins of the cells and coagulates them.

In some cases, it can sensitize the skin; therefore, its use requires caution. With increased sweating, it serves as a means of reducing the secretion of sweat glands, as well as an antiseptic in the form of 0.5-1% solutions.

In the presence of skin irritation and cracks, formalin is contraindicated.

It would be advisable to completely abandon the introduction of formalin into cosmetical tools, due to its carcinogenicity.

Furacilin-5-nitro-2-fufurilen-semicarbazone-yellow fine-crystalline powder of slightly bitter color, a strong antiseptic that acts on gram-positive and gram-negative microbes, large viruses and some protozoa. Inhibits the growth of microorganisms that have become resistant to antibiotics and sulfonamides. Furacilin solutions do not irritate the skin and promote granulation and wound healing. In cosmetics, it was used, especially in combination with sulfur, for the care of oily skin, prone to acne.

Furacilin solutions do not deteriorate from time to time, however, the aqueous solution should be protected from infection by fungi, since furacilin does not have fungicidal properties. Furacilin is considered harmless, but there are reports of leukoderma and graying as a result of its use.

Quinosol [C9H7 (OH) 2N2. H2SO4] 8-hydroxyquinoline sulfate. An extremely strong and harmless antiseptic. At a dilution of 1: 300,000, it inhibits the growth of lower microorganisms, and at a dilution of 1: 40,000, it kills them. An excellent product for cosmetic and hygiene products.

The use of quinzol is highly advisable:

• 1.In products for freckles, spots on the skin and acne (1: 500-1000);
• 2. in disinfectants intended for use after shaving for the purpose of disinfection, elimination of irritation and skin rashes and as a hemostatic (1: 1000-2000);
• 3. against dandruff and hair loss (1: 500);
• 4. for shampooing and skin disinfection (1: 1000);
• 5.in soaps (1: 200);
• 6.Anti-sweat (1: 1000);
• 7. for burns (1: 1000), especially when mixed with thymol;
• 8. as a preservative for fats and water preparations (1: 5000-10000).

Zinc sulfur carbolic or zinc carbol sulfur Zn (C6H4OHSO3) 2 + 7H2O. It is added to lotions as an antiseptic for disinfecting the skin after shaving.

Hydrogen peroxide (H2O2). It is used as an energetic oxidizing, disinfecting, antiseptic and bleaching (bleaching) agent for freckles and spots on the skin, in dental preparations for whitening teeth, for bleaching hair. In the latter case, it brings undoubted harm, since the hair from the frequent use of hydrogen peroxide becomes thin, brittle and brittle.

The antiseptic effect of hydrogen peroxide is based on the fact that in the light or on contact with organic matter (skin, hair), it decomposes into water and oxygen, released in the form of an energetic allotropic form - ozone.

Bromothymol С10Н13ОBr - a product of thymol bromination, is introduced into liquid preparations for air freshening and disinfection in dilution with alcohol 1: 5000. At this concentration, bromothymol has no perceptible odor.

Table- Requirements for antiseptics and disinfectants.

Requirements for antiseptic and disinfectants
Required properties	Invalid properties
A wide range of cidal action (should destroy bacteria, viruses, spores, protozoa, fungi)	Damage or destruction of objects and objects, corrosion of tools
High microbiological efficiency	Irritation and sensitization of human tissues
Sufficient activity in liquid media organism, in the presence of decay products, in acidic and alkaline environments (resistance)	Impaired wound healing
Fast penetration into tissues and fast action (required exposure)	Loss of disinfecting qualities during storage
Compatibility with other antiseptics and disinfectants	Severe and toxic reactions during absorption into the blood and dysfunction of the macroorganism in humans and pets
Safety for staff and patients	Ignition and explosion hazard
Easy to prepare and use	High price

Many microorganisms surround a person. There are beneficial ones that live on the skin, mucous membranes and in the intestines. They help to digest food, participate in the synthesis of vitamins and protect the body from pathogenic microorganisms. And there are a lot of them too. Many diseases are caused by the activity of bacteria in the human body. And the only way to deal with them is with antibiotics. Most of them have a bactericidal effect. This property of such drugs helps to prevent the active multiplication of bacteria and leads to their death. Various remedies with this effect are widely used for indoor and outdoor use.

What is bactericidal action

This property of drugs is used to destroy various microorganisms. Various physical and chemical agents possess this quality. The bactericidal effect is their ability to destroy bacteria and thereby cause their death. The speed of this process depends on the concentration active substance and the number of microorganisms. Only when using penicillins, the bactericidal effect does not increase with an increase in the amount of the drug. Possess bactericidal action:

Where are such funds required?

The bactericidal effect is the property of certain substances that a person constantly needs in economic and household activities. Most often, such drugs are used to disinfect premises in children's and medical institutions, and catering establishments. They are used for processing hands, dishes, equipment. Bactericidal preparations are especially needed in medical institutions, where they are used constantly. Many housewives use such substances in everyday life for treating hands, plumbing and flooring.

Medicine is also an area where bactericidal drugs are used very often. External antiseptics, in addition to treating hands, are used to cleanse wounds and fight infections of the skin and mucous membranes. Chemotherapy drugs are still the only treatment for various infectious diseases caused by bacteria. The peculiarity of such drugs is that they destroy the cell walls of bacteria without affecting human cells.

Antibiotics with bactericidal action

These drugs are most commonly used to fight infection. Antibiotics are divided into two groups: bactericidal and bacteriostatic, that is, those that do not kill bacteria, but simply prevent them from multiplying. The first group is used more often, since the effect of such drugs occurs faster. They are used in acute infectious processes, when there is an intensive division of bacterial cells. In such antibiotics, the bactericidal effect is expressed in the violation of protein synthesis and the prevention of the construction of the cell wall. As a result, bacteria die. These antibiotics include:

Plants with bactericidal action

Some plants also have the ability to kill bacteria. They are less effective than antibiotics, act much more slowly, but are often used as an adjunct treatment. The following plants have a bactericidal effect:

Local disinfectants

Such preparations, which have a bactericidal effect, are used for treating hands, equipment, medical instruments, floors and plumbing. Some are safe for the skin and are even used to heal infected wounds. They can be divided into several groups:

Rules for the use of such drugs

All germicidal agents are powerful and can cause serious side effects. When using external antiseptics, be sure to follow the instructions and avoid overdose. Some disinfectants are very toxic, for example chlorine or phenol, so when working with them you need to protect your hands and respiratory system and strictly observe the dosage.

Oral chemotherapy drugs can also be dangerous. Indeed, together with pathogenic bacteria, they destroy beneficial microorganisms. Because of this, the patient's work is disrupted. gastrointestinal tract, there is a lack of vitamins and minerals, immunity decreases and allergic reactions appear. Therefore, when using bactericidal drugs, you must follow some rules:

• they must be taken only as directed by a doctor;
• the dosage and regimen of administration are very important: they act only if there is a certain concentration of the active substance in the body;
• treatment cannot be interrupted ahead of time, even if the condition has improved, otherwise the bacteria can develop resistance;
• it is recommended to drink antibiotics only with water, so they work better.

Bactericidal drugs only affect bacteria, destroying them. They are ineffective against viruses and fungi, but destroy beneficial microorganisms. Therefore, self-medication with such drugs is unacceptable.

The global effect of antibiotics on bacteria or other microorganisms can be expressed in two forms: bactericidal and bacteriostatic effects. With the bactericidal action of the antibiotic, the growth of bacteria does not resume. Antibiotics that destroy the cell wall. The invention relates to medical and veterinary bacteriology and can be used to differentiate antibiotics for bactericidal bacteriostatic action.

The bacteriostatic effect of drugs is a temporary suppression of the ability of microorganisms to reproduce in the body. Antibiotics such as various penicillins, streptomycin, neomycin, kanamycin, vancomycin, polymyxin have a bactericidal effect. When the antibiotic is removed from the environment, microorganisms can develop again. In most cases, in the treatment of infectious diseases, the bacteriostatic effect of antibiotics in combination with the body's defense mechanisms ensures the patient's recovery.

Antibiotic Use in Veterinary and Livestock - The use of antibiotics in veterinary medicine began immediately after their discovery. ANTIBIOTICS are chemicals produced by microorganisms that can inhibit the growth and kill bacteria and other microbes. In the first case, the microorganisms die, and then they talk about the bactericidal effect of this preservative, in the second, there is a deep inhibition of the vital functions of the microorganism.

For the manifestation of their action, antibacterial drugs in most cases must penetrate into the cell, and the main barrier in their path is the cell wall of the microorganism. When identifying a microorganism, it is necessary to use antibacterial agent, which has the narrowest spectrum of action. This means that it should have a damaging effect in relation to the microorganism only, without affecting the macroorganism.

For many antimicrobial agents, the intimate mechanism of action has not been fully elucidated. Antimicrobial agents can have a bactericidal or bacteriostatic effect in terms of the depth of their effect on a microorganism. The bactericidal effect leads to the death of the microorganism, for example, beta-lactam antibiotics, aminoglycosides act. The bacteriostatic effect consists in the temporary suppression of the growth and reproduction of microorganisms (tetracyclines, sulfonamides).

Bacteriostatic drugs should not be combined with bactericidal drugs. However, the concepts of bactericidal and bacteriostatic are not absolute, since very often an increase in the concentration of a bacteriostatic drug can give a bactericidal effect.

There are two main mechanisms of antibiotic action:

A certain influence on the type of action of antibiotics is exerted by the microorganism, the properties of the antibiotic, as well as their concentration. However, the most accessible and evidence-based bactericidal type of action is the lack of the ability of cells to grow and multiply after removal of the antibiotic. These enzymes are called extended-spectrum beta-lactamases.

With the bacteriostatic action of the antibiotic on bacteria, after the addition of penicillinase, bacterial growth appears in those wells where it was not found after the second stage of the study. Example 1. Determination of the bactericidal and bacteriostatic effect of the sodium salt of benzylpenicillin on museum cultures of bacteria. However, for St. aureus, Y. pseudotuberculosis and B. cereus - highly sensitive to antibiotics, this difference did not exceed two times.

Possibility of using antibiotics in pregnant and lactating women

In a parallel row with added penicillinase, bacterial growth (yellowing and turbidity of the medium) was observed in all wells, including at the maximum concentration of the antibiotic. A detachable 6th T-va has been added to all holes. After 6 hours, a delay in bacterial growth was found in the first three wells at the concentration of the antibiotic. 3. The method according to claim 1, characterized in that the concentration of the antibiotic is reduced by the serial dilution method.

How can antibiotics be administered to the body?

1) Bactericidal mechanism- complete suppression of the growth of bacteria by acting on the vital cellular structures of microorganisms, therefore, causing their irreversible death. If you do not follow the full course of treatment and stop taking the bacteriostatic antibiotic early, your symptoms will return. After taking the antibiotic, it appears in the blood, and then in a specific organ.

Currently, there is an acute problem of antibiotic resistance of microorganisms (resistance of microorganisms to the action of antibacterial drugs). In small doses, antibiotics are dangerous and affect the formation of bacterial resistance. Milk and dairy products should be taken no earlier than 4 hours after taking the antibiotic or completely abandoned during the course of therapy. For example, the action hormonal contraceptives decreases when taking antibiotics.

According to statistics, antibiotics in Russia are received by up to 70-85% of children with pure viral infections, that is, antibiotics were not shown to these kids. Also, one cannot hesitate in prescribing antibiotics for mycobacterial infection (tuberculosis), where specific antibacterial drugs are key in the treatment regimen. This is primarily due to the inevitable side effects drugs of any degree of severity. Antibiotics are a group of organic substances of natural (natural) or semi-synthetic origin that have the ability to destroy or slow down the growth of bacteria, fungi and tumors.

What is an antibiotic?

This substance is a natural antibiotic - a chemical weapon of the microworld. Indeed, the development of antibiotics is one of the most advanced methods of competition between microorganisms in nature.

Features of taking antibiotics:

But this was only the beginning of the era of antibiotics. At the same time, it turned out that some antibiotics can be used to treat fungal infections or to destroy malignant tumors. The most important point in understanding the phenomenon of antibiotics is to determine the horizon of their action. And vice versa: antibiotics are completely ineffective against viruses, which are known to be subcellular microorganisms.

Under bacteriostatic action, the death of microorganisms does not occur, only the cessation of their growth and reproduction is observed. One of the most important signs for antibiotics is the type of their action on microorganisms - bacteriostatic and bactericidal (Navashin S.M., Fomina I.P. Rational antibiotic therapy. The aim of the invention is to increase the reliability of the method and speed up the determination with differentiation of the type of bacteriostatic and bactericidal action of antibiotics.